If you bump into someone who claims to know everything about God…run.
We cannot know everything about God, in fact what we do know is nothing in comparison to the totality of his being. It’s one star in a universe of billions. Our minds, as they are, cannot comprehend the tiniest fraction of who God is.
We cannot put God on our examination table and dissect him, and frankly I don’t understand the Christians who want to try. If any of us could satisfactorily explain God, I think we would all be in trouble. Because, that would mean that God is not that big of a deal, not that great, not that holy, not that merciful, not that powerful.
For me, it’s a comfort to know that God is so powerful that he is impossible for us to comprehend, so holy that a lifetime of sacrificial giving by a Mother Teresa looks like a pile of filthy rags in comparison, so loving that there are no words in any language to describe him. If God were explainable by humans he would not be a God worth putting our faith in, let alone worshiping.
We can know, however, as much as God wants us to know, as much as he gave us the ability to comprehend. We are on a need to know basis with God. He could tell us everything–but then he’d have to kill us.
Parents understand that their three year old needs to know that they can’t run into the street because they could get hurt. They don’t need to know the details of what a car can do to their little bodies, the intricacies of the human anatomy and what blunt force trauma can do to each of their organs. As the child grows we teach them what they need to know to get through their next phase of life until they become adults.
We are God’s children and we are told what we need to know to get home to him, where I believe we will become adults, given knowledge that would overwhelm our current brain capacity. That doesn’t mean that we will ever know everything about God. Compared to him we will always be children, but compared to what we are now we will have grown up.